短期地膜覆盖以幸干旱区春小麦生长发育和产量的影响

在黄土高原半干旱地区，以旱地春小麦进行短期地膜覆盖试验，结果表明：地膜覆盖可明显提高小麦生长前期的土壤温度，有效防止春季低温对作物的伤害，促进分蘖成穗，并显著提高结实小穗数和穗粒数，从而达到增产目的。播种后1－30d左右为旱地春小麦最佳覆膜时间。覆膜时间增长，增温效果减弱，产量有下降的趋势。

Effects of Shortterm Plastic Film Mulching on the Growth and Yield of Spring Wheat in the Semiarid Region.

The field trial of plastic film mulching on dryland spring wheat was conducted in the semiarid region of Loess Plateau. The results showed that:the soil temperature during the early growth period of spring wheat was raised markedly under plastic film mulching conditions, which avoided the injury on spring wheat by spring low temperature and increased the number of effective tillers, fertile spiklets and kernels per ear significantly, thus raised the grain yield of spring wheat. The best period in plastic film mulching was during 1-30 days after sowing of dryland spring wheat in the semiarid region of Loess Plateau. When the time of mulching was longer, the temperatureincreased effect decreased, and the yield had a tendency to decling.